Congrats for the new version. Lots of new features to check out. Great!
One minor cosmetic thing. In 2.6, dialog boxes (like the “Save Changes?” box when closing the app) are hidden when Renoise is running fullscreen. When I hit Alt+Tab, the dialog window comes to the foreground again.
Also tested the other commonly used WMs again, and they all seemed to work now. Well, at least without show stoppers:
metacity, compiz, mutter, kwin, xfwm4, dwm, awesome and plain X (no WM)
There are small problems here and there in some of them, but we can’t fix everything for every single WM on this planet.